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by SCHiM 3543 days ago
tl/dr: U.S. Military spy satellite camera calibration.
4 comments

Right. Since each "mysterious" X was equipped with a "US Army Corps of Engineers" brass plate, it was kind of obvious they were calibration targets for something military. The article says "focusing", but they were probably used to get more precise orbital elements for satellites. This was pre-GPS, and calibration across geography on a planetary scale was tough.
> The article says "focusing", but they were probably used to get more precise orbital elements for satellites. This was pre-GPS, and calibration across geography on a planetary scale was tough.

My guess is that they served a function for calibrating ground control points rather than orbital elements. Even today, NORAD publishes orbital elements (TLEs) for spacecraft deduced by radar (and also optical means). I think other radio ranging techniques were also used before GPS. Trying to point at Earth-fixed point with only an inertial attitude (without a position/velocity) seems really tough.

Today, lots of CubeSats don't have GPS, so they eagerly await getting TLEs from NORAD. It seems like this Twitter is always the first with new data:

https://twitter.com/TSKelso

Left open to rampant speculation it could be test targets for bombing.
Yes, indeed but read it anyways! ;)

It's not too long IMO and the human element of the story is lost in this summary.

Too long for me! Just here to waste a minute and the TLDR does me a service.
Did anybody find one on Google Maps in Satellite mode?
I found two: 32.807001, -111.722184 and 32.791790, -111.705250 I'd like to find more to see the 'grid' mentioned in the article.
The description there implies that the other crosses no longer remain, but I was able to find the first 3 I looked for just by looking for midpoints between other markers on the grid.
Yes, it definitely doesn't have them all. I've found more too. Perhaps the map maker got bored.
32.807147, -111.688916
Hah the first one is next door to a gun range.
> "This [X] we're standing on right now helped protect us from nuclear war," Owen says.

Um no. It just helped the US know where shit is. They didn't keep us safe. Mutually assured destruction did. That's why every war since then has been a proxy war.

If anything, programs like this poured massive amounts of money into expanding out out of control military and probably caused the expansion of wars into areas, leading to the deaths of countless civilians in the former USSR nations.

I mean, isn't that a bit pedantic? If you go down that route, MAD didn't keep us safe either, it's our enemies belief/knowledge that we had weapons of mass destruction, that kept us safe. etcetcetc

It's all part of it. Without intelligence (from dozens of source) to act upon, and Americas enemies believing we could find meaningful targets and/or hit them, MAD wouldn't really exist. Same goes for not having the tech to launch the nukes. Or a hundred other things.

It all helped, to one degree or another, and that is all they said. "This [X] we're standing on right now helped protect us from nuclear war".

Am i missing your point?